This invention concerns a nozzle carrier of a windshield washing apparatus for vehicles, particularly for vehicle headlights, having an outer cylinder, a telescoping inner cylinder in the outer cylinder with a jet nozzle at an end portion thereof which can be shoved out of the outer cylinder, first and second plungers for defining and pressing towards the jet nozzle a particular quantity of washing liquid, and with a valve in series with the jet nozzle which opens when the jet nozzle is in an outwardly-shoved position.
Such a nozzle carrier for a windshield washing apparatus for vehicles, particularly for vehicle headlights, is disclosed in German Patent Publication DE 41 43 316. This windshield washing apparatus has, exteriorly of outer and inner cylinders of the nozzle carrier, a chamber which serves to store a particular quantity of washing liquid. The particular quantity of washing liquid can be pressed out of the chamber into the inner cylinder of the nozzle carrier by compressed air. When this is done, the inner cylinder is shoved from the outer cylinder to place a jet nozzle in its operational position by pressure of the washing liquid. A valve that is connected in series with the jet nozzle opens upon a particular pressure of the washing liquid being executed. Only a small amount of washing liquid can be stored in the inner cylinder. Thus, in order to wash a windshield of a vehicle headlight a washing procedure must be repeated many times. Further, in addition to serving as a storage container for the washing liquid, the external chamber for the particular quantity of washing liquid is necessary because the particular quantity of washing liquid is pressed into the nozzle carrier by compressed air. Further, in addition to the valve which is in series with the jet nozzle, two shoving valves and two check valves are necessary. A first plunger is movably mounted in the inner cylinder and a second plunger is movably mounted in the outer cylinder. The two plungers are connected with one another by a rod-like pull element. The rod-like pull element is tubularly shaped and thereby has a bore, or passageway, for the washing liquid. After the external chamber is filled with the particular quantity of washing liquid, compressed air can, upon a shoving valve opening, enter the chamber and press the washing liquid through the passageway of the pull element into the inner cylinder. When this is done, the inner cylinder moves out of the outer cylinder. After the particular quantity of the washing liquid is pressed into the inner cylinder, the inner cylinder carries the first plunger with it a short distance by impact. The first plunger pulls with it, via the pull element, the second plunger, which opens a shoving valve on its face directed away from the jet nozzle. After the shoving valve is opened a check valve on the first plunger closes the passageway of the pull element and the compressed air presses against the face of the second plunger directed away from the jet nozzle. Upon a particular pressure being reached, an valve in series with the jet nozzle is opened and the first and second plungers press, by means of being shoved toward the jet nozzle, the washing liquid out of the jet nozzle. Upon completion of this spraying process the inner cylinder impinges on a contact which closes the shoving valve which is positioned between a compressed air source and the chamber, Thereafter, the second plunger is no longer engaged by compressed air and a spring element positioned between the inner cylinder and the outer cylinder shoves the inner cylinder into the outer cylinder and the first and second plungers to their starting positions. During this time a pump supplies washing liquid from a storage container into the chamber and thereby opens a check valve of the chamber.
German Patent Publication DE 26 55 531 discloses a movable, or shovable, washing apparatus for vehicles in which an external cylinder arranged between a storage container for washing liquid and a jet nozzle stores such a quantity of washing liquid that the stored washing liquid is sufficient for an entire washing process. The particular quantity of washing liquid is pressed by a plunger to a jet nozzle, with the plunger being moved in the cylinder by pressure of a following flow of washing liquid.
It is an object of this invention to provide a nozzle carrier of the type described in the opening paragraph above for a windshield washing apparatus for vehicles, particularly for vehicle headlights, in which the particular quantity of washing liquid for an entire washing procedure is sufficient and need not be intermediately stored externally of a telescoping cylinder. Further, pressure of the washing liquid should cause the inner cylinder to be pressed out of the outer cylinder as well as the particular quantity of washing liquid to be pressed out of the jet nozzle.